Researchers from the World Health Organisation (WHO) recently announced that coffee and herbal tea consumed at normal serving temperatures do not cause cancer and should not be labelled as carcinogenic.
The findings have knocked the cancer risk of these drinks down to zero, some 25 years after the WHO classified coffee as a possible carcinogen that could lead to bladder cancer. But the scientists still say that drinking extremely hot beverages might cause cancer of the oesophagus.
The conclusion was drawn after 23 scientists from the WHO's International Agency for Research on Cancer (IARC) reviewed more than 1,000 studies on coffee’s link to cancer. They report that, "there was inadequate evidence for the carcinogenicity of coffee drinking overall".
This is great news for coffee lovers everywhere, which - statistically speaking - is a whole lot of us. Americans alone spent more than $74.2 billion on coffee in 2015, which isn’t that surprising, considering that coffee is consumed more than tap water in the US. In 2014, over 150 million 60-kilogram (132-pound) bags of coffee were ground up and drank globally.
So now we can all continue chugging our lattes without worrying too much about them causing us increased risk of cancer. Unless, as the researchers note, you like your coffee extremely hot.
While the team didn’t go into detail about what "extremely hot" actually means, they do say that coffee consumed at "serving temperature" is fine. That means somewhere around 65 degrees Celsius (150 degrees Fahrenheit).
It’s not that the coffee suddenly becomes a carcinogen when heated to a high temperature, though. The researchers instead think that repeated scalding of the throat might lead to the formation of tumours, though evidence of this is currently limited.
"These results suggest that drinking very hot beverages is one probable cause of oesophagal cancer and that it is the temperature, rather than the drinks themselves, that appears to be responsible," IARC director Christopher Wild told AFP.
To make a good cup of coffee, the water temperature while brewing should be somewhere between 90.5 degrees Celsius (195 degrees Fahrenheit) and 96 degrees Celsius (205 degrees Fahrenheit). When served, that temperature drops rather quickly. If it didn’t, the coffee would be too hot to comfortably drink, which is what you should avoid.
The basic rule of thumb here is that if the coffee burns you, wait a few minutes. Not only will this possibly reduce your risk of oesophageal cancer, it will make for a better coffee drinking experience, because who wants a side of pain with their morning cup of Joe?
While the WHO media team didn't mention anything about the potential health benefits of coffee in their change in recommendations, other institutes have pointed out that coffee could actually prevent many types of cancers.
"Coffee’s possible link to cancer is a well-studied one, with over 1,000 studies on the topic. Early in the research, some studies hinted that coffee might increase cancer risk. Larger and more well-designed studies now suggest the opposite: it may be protective for some cancers."
Cancer isn’t the only disease that coffee could reduce. Earlier this year, researchers from the University of Southampton in the UK found positive results with liver disease, concluding that "having two cups of coffee a day appears to reduce the chances of developing the disease by 44 percent, based on data from 430,000 individuals spread over nine studies", David Nield reported for us back in February.
Let's be clear though - despite the wealth of research into the potential health benefits of coffee, nothing definitive has yet been found. It could be that we're trying really hard to find something beneficial in drinking coffee, because that would be very convenient, given how many of us do it. So we have to remain skeptical for now.
As the research continues, we might find real health benefits in our coffee drinking, but we really don’t need more of an excuse other than it tastes delicious and we're all really, really tired.
A summary of the IARC's findings was published in The Lancet Oncology.